Vasculitides are a set of pathologies that can affect one or several organs, in the short and long term. They are associated with various etiologies, among which paraneoplastic syndromes and medications stand out. Although everyday cancer therapies are more directed against a therapeutic target, their use can cause a wide spectrum of complications. Some treatments against human epidermal growth factor 2 (HER2) have been associated with cutaneous and pulmonary vasculitis. We present the first case of Henoch-Schönlein purpura associated with the use of T-DM1 in a patient with HER2 breast cancer.